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A stable QTL QPm.caas-3BS for adult-plant resistance to powdery mildew was mapped in an interval of 431 kb, and candidate genes were predicted based on gene sequences and expression profiles. Powdery mildew is a devastating foliar disease occurring in most wheat-growing areas. Characterization and fine mapping of genes for powdery mildew resistance can benefit marker-assisted breeding. We previously identified a stable quantitative trait locus (QTL) QPm.caas-3BS for adult-plant resistance to powdery mildew in a recombinant inbred line population of Zhou8425B/Chinese Spring by phenotyping across four environments. Using 11 heterozygous recombinants and high-density molecular markers, QPm.caas-3BS was delimited in a physical interval of approximately 3.91 Mb. Based on re-sequenced data and expression profiles, three genes TraesCS3B02G014800, TraesCS3B02G016800 and TraesCS3B02G019900 were associated with the powdery mildew resistance locus. Three gene-specific kompetitive allele-specific PCR (KASP) markers were developed from these genes and validated in the Zhou8425B derivatives and Zhou8425B/Chinese Spring population in which the resistance gene was mapped to a 0.3 cM interval flanked by KASP14800 and snp_50465, corresponding to a 431 kb region at the distal end of chromosome 3BS. Within the interval, TraesCS3B02G014800 was the most likely candidate gene for QPm.caas-3BS, but TraesCS3B02G016300 and TraesCS3B02G016400 were less likely candidates based on gene annotations and sequence variation between the parents. These results not only offer high-throughput KASP markers for improvement of powdery mildew resistance but also pave the way to map-based cloning of the resistance gene.

In this work, the surface band edge of the BiVO4 photoanode is modulated by an in situ gas-phase cation exchange method, in which some of the Bi atoms on the surface are replaced by V atoms to form a V-rich surface.

The vital issue for semiconductor pressure sensors is how to improve the sensitivity of their piezoresistive behavior. In this work, aiming to substantially promote the sensitivity, ZnO/SiC nanowire heterojunctions with various ZnO piezoelectric shell thicknesses were constructed by adjusting the depositing times of atomic layer deposition (ALD). It was found that the thicknesses of coupled ZnO nanolayers played a profound effect on the response of the heterojunctions to the change of stresses, representing the tailored piezoresistive behaviors. Accordingly, the piezoresistive coefficient was optimized to ~ 9.47 × 10–11 Pa−1 with an enhanced ΔR/R0 value of ~ 0.88, once the ZnO nanolayer thickness is fixed at ~ 20 nm, superior to most of pressures sensors based on SiC nanomaterials. This work may provide a novel strategy for exploring advanced SiC-based pressure sensors by coupling with suitable thickness of the piezoelectric nanolayer to improve piezoresistive behaviors. The tailored piezoresistive performance of ZnO/SiC nanowire heterojunctions with a adjusted shell thicknesses of ZnO piezoelectric nanolayers was reported, which had an enhanced piezoresistive coefficient of 9.47 × 10–11 Pa−1 and a ΔR/R0 of 0.88.

Significance The present work might be significant for exploring advanced K-ion batteries with superb rate capability and cycle stability toward practical applications. The as-assembled K-ion half cell exhibits an excellent rate capability of 428 mA h g −1 at 100 mA g −1 and a high reversible specific capacity of 330 mA h g −1 with 120% specific capacity retention after 2,000 cycles at 2,000 mA g −1 , which is the best among those based on carbon materials. The as-constructed full cell delivers 98% specific capacity retention over 750 cycles at 500 mA g −1 , superior to most of those based on carbon materials that have been reported thus far.

Purpose This study aimed to describe the epidemiologic characteristics of fracture in the elderly during the COVID-19. Methods This was a retrospective multi-centre study, which included patients who sustained fractures between 20 January and 19 February 2020. The collected data included patients' demographics (age and gender), injury-related (injury type, fracture location, injury mechanism, places where fracture occurred), and treatment modality. SPSS 23.0 was used to describe the data and perform some analysis. Results A total of 436 patients with 453 fractures were included; there were 153 males and 283 females, with an average age of 76.2 years (standard deviation, SD, 7.7 years; 65 to 105). For either males or females, 70-74 years was the most commonly involved age group. A total of 317 (72.7%) patients had their fractures occurring at home. Among 453 fractures, there were 264 (58.3%) hip fractures, accounting for 58.3%. Fall from standing height was the most common cause of fracture, making a proportion of 89.4% (405/453). Most fractures (95.8%, 434/453) were treated surgically, and 4.2% (19/453) were treated by plaster fixation or traction. Open reduction and internal fixation (ORIF) was the most used surgical method, taking a proportion of 49.2% (223/453). Conclusion These findings highlighted the importance of primary prevention (home prevention) measures and could be used for references for individuals, health care providers, or health administrative department during the global pandemic of COVID-19.

Photoelectrochemical (PEC) splitting of water into H2 and O2 by direct use of sunlight is an ideal strategy for the production of clean and renewable energy, which fundamentally relies on the explo...

Silicon carbide (SiC) is recognized as one of the most important candidates of third generation semiconductors with totally superior physical/chemical properties and exciting applications in opto/electronic devices. In the present work, we report the exploration of high-performance blue-light photodetectors on both rigid and flexible substrates by using SiC nanoarrays, which are aligned by dielectrophoresis. The rise and decay times of the photodetector assembled on a rigid (i.e., SiO2/Si) substrate are ∼0.39 and 0.56 s, respectively, with an external quantum efficiency of 3394%, which suggested that the SiC nanoarray photodetector has high sensitivity, fast responsivity and excellent reproducibility to light irradiation with a wavelength of 445 nm. Meanwhile, 73% of the maximum photocurrent response can be maintained after 6 months. Furthermore, the as-constructed flexible photodetector based on the polyethylene terepthalate (PET) substrate was highly stable against repeated bending, demonstrating that the as-constructed SiC photodetector was robust with high flexibility and electrical stability.

In the present study, the field emission (FE) behaviors of CsPbI3 nanobelts were reported, which were synthesized via a one-step facile solvothermal method. The obtained CsPbI3 nanobelts were single crystalline in nature with a typical growth direction along [100]. It was disclosed that the valence band maximum (VBM) and conduction band minimum (CBM) vs. vacuum level of the CsPbI3 nanobelts were located at −4.86 and −2.16 eV, respectively, and their work function (Φ) was calculated to be of 3.56 eV. The as-grown CsPbI3 nanobelts exhibited outstanding field emission (FE) characteristics with a low turn-on field (Eto) of ∼2.62 V μm−1 and a high field enhancement factor of 3553, representing their potential applications in field emission display devices.

Genetic diversity, population structure, LD decay, and selective sweeps in 687 wheat accessions were analyzed, providing relevant guidelines to facilitate the use of the germplasm in wheat breeding. Common wheat (Triticum aestivum L.) is one of the most widely grown crops in the world. Landraces were subjected to strong human-mediated selection in developing high-yielding, good quality, and widely adapted cultivars. To investigate the genome-wide patterns of allelic variation, population structure and patterns of selective sweeps during modern wheat breeding, we tested 687 wheat accessions, including landraces (148) and cultivars (539) mainly from China and Pakistan in a wheat 90 K single nucleotide polymorphism array. Population structure analysis revealed that cultivars and landraces from China and Pakistan comprised three relatively independent genetic clusters. Cultivars displayed lower nucleotide diversity and a wider average LD decay across whole genome, indicating allelic erosion and a diversity bottleneck due to the modern breeding. Analysis of genetic differentiation between landraces and cultivars from China and Pakistan identified allelic variants subjected to selection during modern breeding. In total, 477 unique genome regions showed signatures of selection, where 109 were identified in both China and Pakistan germplasm. The majority of genomic regions were located in the B genome (225), followed by the A genome (175), and only 77 regions were located in the D genome. EigenGWAS was further used to identify key selection loci in modern wheat cultivars from China and Pakistan by comparing with global winter wheat and spring wheat diversity panels, respectively. A few known functional genes or loci found within these genome regions corresponded to known phenotypes for disease resistance, vernalization, quality, adaptability and yield-related traits. This study uncovered molecular footprints of modern wheat breeding and explained the genetic basis of polygenic adaptation in wheat. The results will be useful for understanding targets of modern wheat breeding, and in devising future breeding strategies to target beneficial alleles currently not pursued.

Limited light harvesting and charge collection are recognized as grand challenges for the exploration of highly efficient TiO2 photoanodes. To overcome these intrinsic shortcomings, we reported the...

Making field emitters with both low turn-on field (Eto) and high current emission stability is one of the keys to push forward their practical applications. In the present work, we report the exploration of high-performance field emitters with designed sharp corners around SiC nanowires for fundamentally enhanced electron emission sites. The sharp corners with tailored densities are rationally created based on a facile etching technique. Accordingly, the emission sites and nanowires are integrated into a single-crystalline configuration without interfaces, which could offer the emitters with a robust structure to avoid the structural damage induced by the generated Joule heat and electrostatic forces over long-term field emission (FE) operation. Consequently, the Eto of the as-fabricated SiC field emitter is low down to 0.52 V/μm, which is comparable to the state-of-the-art one ever reported. Moreover, they have high electron emission stability with a current fluctuation of just 2% over 10 h, representing their promising applications in FE-based electronic units.

The giant piezoresistance effect (PRE) of semiconductors as featured by a high gauge factor (GF) is recognized as the prerequisite for realizing optimal pressure sensors with desired high sensitivity. In this work, we report the discovery of giant PRE in SiC nanobelts with a record GF measured using an atomic force microscope. The transverse piezoresistance coefficient along the [111] direction reaches as high as -312.51 × 10-11 pa-1 with a corresponding GF up to -1875.1, which is twice more than the highest value ever reported on SiC nanomaterials. The first-principles calculations reveal that B doping turns the acceptor states in the bandgap into deeper impurity levels, which makes the major contribution to the observed giant piezoresistance behavior. Our result provides new insights on designing pressure sensors based on SiC nanomaterials.

Mollisols are extremely important soil resource for crop and forage production. In northeast China, it is a major land use management practice from dry land crops to irrigated rice. However, there is few data regarding soil quality and microbial composition in Mollisols during land use transition. Here, we analyzed the upper 30 cm of soil from land with more than 30 years of paddy use and from adjacent areas with upland crops. Our results showed that land use and soil depth had a significant effect on soil properties and enzyme activities. Soil moisture (SM) and soil organic carbon (SOC) contents were substantially higher in paddy fields than in upland crop lands, while nitrogen-related enzyme activities were lower. Following the land use change, bacterial diversity was increased and bacterial community composition changed. Taxonomic analyses showed that Proteobacteria, Chloroflexi, Firmicutes, and Bacteroidetes were the dominant phyla present. At family level, Gemmatimonadaceae decreased with land use change, while Syntrophorhabdaceae and Syntrophacea that play a part in methane cycling and nitrifying bacteria such as Nitrospiraceae increased, indicating that the structure and composition of the bacterial community might be a promising indicator of Mollisol health. Redundancy analysis indicated that land use type had a stronger effect on the soil bacterial community composition than soil depth. Additionally, bacterial community composition was closely associated with soil parameters such as soil moisture, pH, SOC, NO3−-N, and NH4+-N. Overall, land use change affects the physical and chemical properties of the soil, resulting in changes in the composition of the soil bacterial community and flora. These changes could provide a view of the bacterial community assembly and functional shifts following land use change.

We report, for the first time, the exploration of an efficient photoanode based on an N-doped 4H-SiC nanochannel array for photoelectrochemical (PEC) water splitting, which is fabricated through an anodic oxidation approach. The SiC photoanode yields a high photocurrent density of 2.41 mA cm−2 at 1.4 V vs. Ag/AgCl under 1.5G simulated sunlight. Meanwhile, the as-constructed photoanode presents a fast photoresponse and wide photoresponse wavelength range. The high orientation of SiC nanochannel arrays, the single-crystal nature of the whole SiC film and the incorporated N dopants are responsible for the enhanced PEC performance, with the benefits of substantially improving the light capability and extending the optical absorption edges, as well as promoting transport and separation of photoexcited charge carriers.

Low turn-on fields (Eto) and high current emission stabilities are recognized as two crucial factors for the potential applications of field emission (FE) cathodes. In this work, graphene/SiC (G/SiC) heterojunction nanowire arrays were fabricated through catalyst-assisted pyrolysis of polymeric precursors. Aiming to explore advanced field emitters, G/SiC nanoarrays are designed to grow with a desired architecture including sharp tips, rough surface, incorporated dopants, and well-aligned configurations, which could fundamentally increase the effective emission sites, tailor the band gap structure, fully utilize the local field enhancement effect, and limit the shielding effect. The G/SiC emitters established exceptional FE properties with low and stable Eto of 1.10–1.12 V μm−1 when subjected to various anode–cathode distances, as well as a small current emission fluctuation of ∼3.7% over 5 h and high field enhancement factor up to 6383, which were comparable to the state-of-the-art ones previously reported, representing their totally excellent FE performance.

The conduction band of a BiVO4 semiconductor is slightly lower than the hydrogen (H2) reduction level, indicating that it can’t be used directly for visible-light-driven photocatalytic hydrogen production. In the present work, we report designed BiVO4@TiO2 core–shell hybrid mesoporous nanofibers for photocatalytic hydrogen production under visible irradiation, which are generated through foaming-assisted electrospinning followed by atomic layer deposition (ALD). Such a binary core–shell structure can not only provide a high specific surface area with increased reaction sites, but also cause the formation of a staggered BiVO4@TiO2 heterojunction to promote the charge separation and transfer, leading to a significantly enhanced photocatalytic H2 production efficiency as compared to pure BiVO4.

The third-generation semiconductor silicon carbide (SiC) is identified as one of the vitally important candidate materials to serve as a functional unit that performs stably and reliably under harsh working conditions, with respect to its excellent piezoresistive effects and robust physical/chemical characteristics. In the current work, we put forward the fabrication of SiC nanowires with co-doped N and P elements, which were fabricated via the pyrolysis of a polymeric material. The as-grown nanowires have a typical diameter of ∼260 nm with a 10 surface. The measured transverse piezoresistance coefficient π[10] of the established SiC nanowires increased from 5.07 to −146.30 × 10−11 Pa−1 as the loading forces varied from 24.95 to 130.51 nN. Meanwhile, the corresponding gauge factor (GF) was calculated up to ca. −877.79, which is higher than the values for all SiC nanostructures ever reported. The mechanism concerning the giant negative piezoresistance behavior of SiC nanowire is proposed. The current exploration may pave a new avenue for the development of highly sensitive and robust pressure sensors that could survive under harsh working conditions.

Improving the sensitivity of the piezoresistive behavior of semiconductor nanostructures is critically important because it is one of the keys to explore advanced pressure sensors with desired sensitivity. Herein, we reported a strategy for improving the piezoresistive behavior of SiC nanowire by coupling with the piezoelectric effect of ZnO nanolayers, which were grown by an atomic layer deposition approach. As a result, the detected current of the as-constructed ZnO/SiC heterojunction nanowires is 6 times more than SiC nanowires, suggesting its substantially improved sensitivity. Moreover, the measured Δ

Photoelectrochemical (PEC) splitting of water into H

We developed and validated 56 gene-specific semi-thermal asymmetric reverse PCR (STARP) markers for 46 genes of important wheat quality, biotic and abiotic stress resistance, grain yield, and adaptation-related traits for marker-assisted selection in wheat breeding. Development of high-throughput, low-cost, gene-specific molecular markers is important for marker-assisted selection in wheat breeding. In this study, we developed 56 gene-specific semi-thermal asymmetric reverse PCR (STARP) markers for wheat quality, tolerance to biotic and abiotic stresses, grain yield, and adaptation-related traits. The STARP assays were validated by (1) comparison of the assays with corresponding diagnostic STS/CAPS markers on 40 diverse wheat cultivars and (2) characterization of allelic effects based on the phenotypic and genotypic data of three segregating populations and 305 diverse wheat accessions from China and 13 other countries. The STARP assays showed the advantages of high-throughput, accuracy, flexibility, simple assay design, low operational costs, and platform compatibility. The state-of-the-art assays of this study provide a robust and reliable molecular marker toolkit for wheat breeding programs.

In the present work, we report a ternary WO3/BiVO4/ZnO photoanode with boosted PEC efficiency and stability toward highly efficient water splitting. The type-II WO3/BiVO4 heterojunction arrays are firstly prepared by hydrothermal growth of WO3 nanoplate arrays onto the substrates of fluorine-doped tin oxide (FTO)-coated glass, followed by spin-coating of BiVO4 layers onto the WO3 nanoplate surfaces. After that, thin ZnO layers are further introduced onto the WO3/BiVO4 heterojunction arrays via atomic layer deposition (ALD), leading to the construction of ternary WO3/BiVO4/ZnO photoanodes. It is verified that the ZnO thin layer in the WO3/BiVO4/ZnO photoanode contains abundant oxygen vacancies, which could act as an effective passivation layer to enhance the charge separation and surface water oxidation kinetics of photogenerated carriers. The as-prepared WO3/BiVO4/ZnO photoanode produces a photocurrent of 2.96 mA cm-2 under simulated sunlight with an incident photon-to-current conversion efficiency (IPCE) of ∼72.8% at 380 nm at a potential of 1.23 V versus RHE without cocatalysts, both of which are comparable to the state-of-the-art WO3/BiVO4 counterparts. Moreover, the photocurrent of the WO3/BiVO4/ZnO photoanode shows only 9% decay after 6 h, suggesting its high photoelectrochemical (PEC) stability.

In the present work, we reported the fabrication of CdS decorated mesoporous SiC hollow nanofibers for efficient visible-light-driven photocatalytic hydrogen production. The mesoporous SiC hollow nanofibers were firstly fabricated by electrospinning, followed by hydrothermal treatment to introduce the CdS nanoparticles decorated on the preformed fiber matrix, The resultant CdS/SiC hybrid photocatalysts were systematically characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM) and N2 adsorption. The as-fabricated CdS/SiC hybrids exhibited a robust stability with a release rate up to ~ 124.65 µmol h−1 g−1 for photocatalytic H2 evolution driven by visible light, which was profoundly enhanced for more than 16 times to that of pristine SiC counterparts, and comparable to the state-of-the-art one of SiC-based photocatalysts.

The piezoresistive effect of SiC low-dimensional nanostructures, together with their exclusive benefits of superior mechanical characteristics and could be integrated into the flexible devices that can withdraw large strain, promise to make a wide range of sensing devices application possible in the severe working conditions. In this work, we reported the transverse piezoresistance behaviours of n -type 3 C -SiC nanobelts with selected ( 1 1 ¯ 0 ) top surface and N dopants. The single-crystalline SiC nanobelts were achieved by the means of direct pyrolysis of polymeric precursors without catalysts, which had an average N doping level of ~ 6.02 at% and a typical width-to-thickness ratio of ~ 8. It was disclosed that the transverse piezoresistance coefficient π [ 1 1 ¯ 0 ] reached the maximum 10.29 × 10 –11 Pa −1 at a fixed external stress of 67.03 nN. Correspondingly, the gauge factor (GF) was calculated to be of ~ 61.7, which is higher than all the reported n -type SiC, intrinsic SiC, as well as most of the p -type SiC counterparted. The findings shed light on the fact that present n -type SiC nanobelts have the potential of becoming an outstanding contestant for the development of robust pressure sensors having elevated sensitivities.

Constructing semiconductor heterojunction with optimal structure and composition is highly desired to maximize the solar light utilization for photoelectrochemical (PEC) water splitting. Here, we reported the fabrication of BiVO4@ZnO heterojunction with a novel nanostructure for PEC water splitting via foaming-assisted electrospinning and subsequent atomic layer deposition (ALD) techniques. In such BiVO4@ZnO heterojunction, the isolated BiVO4 nanoparticles were packaged within the ZnO microbelt matrix. During PEC water splitting, the BiVO4 acts as the primary light absorber for wider solar spectral harvesting, and the ZnO prompts the transfer of the photo-excited high-energy electrons, which would render them with prolonged lifetime and enhanced separation of the photogenerated charge carriers. In addition, the microbelts architecture with a hollow channel can also effectively improve the interfacial charge separation and transportation. Accordingly, the PEC performances of BiVO4@ZnO hybrid microbelts were significantly enhanced with a photocurrent density up to ∼0.46 mA cm−2 (at 1.23 V vs. reversible hydrogen electrode (RHE) under simulated sunlight illumination), which is 15.3 times to that of pure BiVO4 counterpart (∼0.03 mA cm−2). The photocurrent density of the BiVO4@ZnO electrode can be further increased to 1.07 mA cm−2 at 1.2 V vs. RHE by adding hole scavenger (NaSO3) in the electrolyte solution under AM 1.5 G irradiation.

Fabrication of SiC nanoarrays is highly recommended owing to the fact that it is the key to push forward them being applied in optoelectronic devices. Nevertheless, majority of the reported works involving the growth of SiC low-dimensional nanostructures were often carried out under the harsh conditions (e.g., high temperatures and/or high pressures), which were teemed as the key obstacle for the accomplishment of their controllable and repeatable growth. In the current work, we reported the controllable and repeatable large-scale fabrication (up to centimeter×centimeter of width × length in area) of well-aligned, free-standing and transparent 4H-SiC nanohole arrays via anodic oxidation of SiC wafers at room temperature and atmospheric pressure conditions. It was discovered that the cycle period of the pulsed voltage played a crucial role in the formation of highly uniform nanohole arrays. In the meantime, the diameters, wall thickness and depth of the nanoholes could be modulated through the customization of the cycle times. Additionally, a possible mechanism was proposed for the formation of nanohole arrays.

In the present work, we reported the fabrication of Fe-doped WO3 nanofibers via a versatile electrospinning method towards efficient photoelectrochemical (PEC) water splitting. The resultant Fe-WO3 nanofibers had a high purity in morphology, and the Fe doping levels within the WO3 nanofibers were controlled in the range from 0.32 to 1.47 at.%, making the band gaps of WO3 nanofibers tailored from 2.92 to 2.8 eV. The incorporated Fe dopants could not only increase the light absorption, but also improve the charge transport and charge transfer efficiencies, bringing an enhanced PEC activity of the WO3 nanofiber photoanodes. The WO3 nanofibers with the optimized 0.32 at.% Fe doping level exhibit the best PEC performance. The mechanism for the enhanced PEC behaviors was proposed.

Currently, all-inorganic CsPbX3 (X = Br, I, Cl) perovskite nanocrystals (NCs) are shining stars with exciting potential applications in optoelectronic devices such as solar cells, light-emitting diodes, lasers, and photodetectors, due to their superior performance in comparison to their organic–inorganic hybrid counterparts. In the present work, we report a general strategy based on a microwave technique for the rapid production of low-dimensional all-inorganic CsPbBr3 perovskite NCs with tunable morphologies within minutes. The effect of the key parameters such as the introduced ligands, solvents, and PbBr2 precursors and microwave powers as well as the irradiation times on the production of perovskite NCs was systematically investigated, which allowed their growth with tunable dimensionalities and sizes. As a proof of concept, the ratio of OA to OAm as well as the concentration of PbBr2 precursor played important roles in triggering the anisotropic growth of the perovskite NCs, favoring their growth int...

Currently, one-dimensional all-inorganic CsPbX3 (X = Br, Cl, and I) perovskites have attracted great attention, owning to their promising and exciting applications in optoelectronic devices. Herein, we reported the exploration of superior photodetectors (PDs) based on a single CsPbI3 nanorod. The as-constructed PDs had a totally excellent performance with a responsivity of 2.92 × 103 A·W–1 and an ultrafast response time of 0.05 ms, respectively, which were both comparable to the best ones ever reported for all-inorganic perovskite PDs. Furthermore, the detectivity of the PDs approached up to 5.17 × 1013 Jones, which was more than 5 times the best one ever reported. More importantly, the as-constructed PDs showed a high stability when maintained under ambient conditions.

Although significant progress has been made in the development of all-inorganic CsPbI3 (X = Br, Cl and I) perovskites, some crucial points typically concerning their stability and toxicity due to the presence of Pb are yet to be addressed. In the present study, we report the growth of qualified all-inorganic CsPbI3 perovskite nanobelts with high yield and purity via a solvothermal route; herein, Sn has been incorporated to substitute Pb to reduce the toxicity of these nanobelts. XPS analyses showed that the Sn-doped CsPbI3 nanobelts were substantially stabilized and exhibited satisfied stability for up to 15 days when maintained under air conditions. The as-constructed photodetectors (PDs) based on a single CsPb0.922Sn0.078I3 nanobelt displayed overall excellent performance with an ultrahigh detectivity of up to 6.43 × 1013 Jones, which was comparable to the best values of all-inorganic perovskite PDs reported to date.

In the current work, we reported the engineering of homo/hetero junctions for boosting the photoelectrochemical (PEC) behaviors of all-inorganic perovskite SrTiO3 (STO) nanofibers. The engineering of these junctions was accomplished via spin-coating and electrospinning, followed by atomic layer deposition (ALD). The introduced STO film leads to the formation of the STO/STO homojunction, which provided an extended contact area to enhance the electron–hole mobility across the interface. Meanwhile, ALD-deposited ZnO allowed for the construction of the STO/ZnO heterojunction, which could build up internal electric fields at the interface to hinder the recombination of electron–hole pairs, causing a totally enhanced photoelectrochemical (PEC) activity. As a proof of concept, at an applied bias of 1.23 V vs. RHE, the photocurrent density of STO nanofibers with engineered homo/hetero junctions was enhanced more than 600 times that of their pristine STO counterpart. At 0 V vs. Ag/AgCl, their photocurrent density was improved up to ∼61.3 μA cm−2 in comparison to 0.12 μA cm−2 of their pristine STO counterpart. Furthermore, their photocurrent stability was increased from 79.62% of their pristine STO counterpart to 98% at 0.1 V vs. Ag/AgCl.

In this work, the failure behavior of a commercial chip size packaging (CSP) with flip chip solder joint was investigated under the coupling condition of thermal cycling and electrical current. The damage behavior of solder joint was real-time monitored through the electrical resistance response. The microstructure evolution under the coupling condition were observed. The failure was classified as three modes, i.e., the cracking within solder on the PCB side (mode I), the cracking along the solder/IMC interface (mode II) and the detachment between the solder and chip due to the complete dissolving of Cu UBM layer (mode III). At low current density the mode I accounted for a large percentage while the mode II and mode III accounted for a large percentage at high current density. Based on the Weibull distribution of failure life, it was found that the mean time to failure sharply decreased with the increasing current density. A lifetime prediction model was constructed for the reliability test under coupling condition of thermal cycling and electrical current.